- Customers tend to spend money.
I think you can safely avoid "tend" on the TOEFL speaking section because this verb implies character judgment and is usually negative:
- He tends to drink too much.
- She tends to gossip.
Please use English well!
The global average TOEFL speaking score is 19. The Japan average score is 15. My students' average top TOEFL speaking score is 23. Why? Because they don't use templates! If you have a clear voice and practice regularly, you should get 23 consistently too.